// atob base64 转换方法
"use strict";
var b64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
var b64re = /^(?:[A-Za-z\d+\/]{4})*?(?:[A-Za-z\d+\/]{2}(?:==)?|[A-Za-z\d+\/]{3}=?)?$/;
export const weBtoa = (string) => {
  string = String(string);
  var bitmap, a, b, c, result = "", i = 0, rest = string.length % 3;
  for (; i < string.length;) {
    if ((a = string.charCodeAt(i++)) > 255 ||
      (b = string.charCodeAt(i++)) > 255 ||
      (c = string.charCodeAt(i++)) > 255)
      throw new TypeError("Failed to execute 'btoa' on 'Window': The string to be encoded contains characters outside of the Latin1 range.");
    bitmap = (a << 16) | (b << 8) | c;
    result += b64.charAt(bitmap >> 18 & 63) + b64.charAt(bitmap >> 12 & 63) +
      b64.charAt(bitmap >> 6 & 63) + b64.charAt(bitmap & 63);
  }
  return rest ? result.slice(0, rest - 3) + "===".substring(rest) : result;
};
export const weAtob = (string) => {
  string = String(string).replace(/[\t\n\f\r ]+/g, "");
  if (!b64re.test(string))
    throw new TypeError("Failed to execute 'atob' on 'Window': The string to be decoded is not correctly encoded.");
  string += "==".slice(2 - (string.length & 3));
  var bitmap, result = "", r1, r2, i = 0;
  for (; i < string.length;) {
    bitmap = b64.indexOf(string.charAt(i++)) << 18 | b64.indexOf(string.charAt(i++)) << 12 |
      (r1 = b64.indexOf(string.charAt(i++))) << 6 | (r2 = b64.indexOf(string.charAt(i++)));
    result += r1 === 64 ? String.fromCharCode(bitmap >> 16 & 255) :
      r2 === 64 ? String.fromCharCode(bitmap >> 16 & 255, bitmap >> 8 & 255) :
        String.fromCharCode(bitmap >> 16 & 255, bitmap >> 8 & 255, bitmap & 255);
  }
  return result;
};